Vacuum tank



Patented Apr. 7, 193 1 s'rarss WILLIAM H. SGHULZE, OF CHICAGO, ILLINOIS, ASSIGNOR TOSTEWART-WARNER (LOR- I-ORA'IION, OF CHICAGO, ILLINOIS, A CORPORATION OF VIRGINIA VACUUM TANK Application filed May 24, 1929. Serial No. 365,631.

The purpose of this invention is to provide a fuel lifting apparatus for supplying an internal combustion engine of a type commonly called a vacuum tank, in which the usual suction controlling valve may be omitted without reducing the pumping or fuel lifting capacity of a tank of a given size, and in which the air admitted for fulcruming the suction tends to permit the vacuum chamber to discharge the lifted liquid into. the reserve chamber ready for supplying the oarbureter, shall be taken directly from the reserve chamber where it is in contact with the gasoline, so that it is more or less impregnated with the fuel vapor and thereby somewhat less liable to disturb the fuel mixture proportions when it passes through the suction connection into the engine intake manifold. The invention consists in the elements and features of construction shown and described as indicated in the claims. 1 V V y In the drawings: 1 I I Figure 1 is a vertical section. of a vacuum tank embodying one form of this invention.

Figure 2 is a top plan view of the same.

In the drawings the vacuum chamber is indicated in entirety at A. The outer body member which comprises the reserve chamber is indicated at B. The two members, A and B, are secured together and closed at the top, except as to connections hereinafter men tioned, by a cap plate, C, which servesthe purpose of securing the two members together by being marginally lapped above the lapped flanges, a and Z), of the members, A and B, and secured by bolts, 10, with suitable packing gaskets, 11, interposed between the lapped flanges to render the vacuum chamber liquid tight.

At-a convenient point in the circumference of the lapped cap and chamber flanges, there is mounted in registered apertures in the flanges, a nipple, 30, which serves as the at inosphere vent orinlet for the reserve chamber. A fuel inlet connection is seen at D discharging through the cap plate in which the fitting, D, is mounted. Such suction connection is seen at E, a fitting also mounted in the cap plate having very closely restriated suction port, as seen at e.

The vacuum chamber, A, has at the bottom a port, 50, for fuel delivery into the reserve chamber, and a valve, 20, mounted interiorly of the vacuum chamber for seating in the direction of outflow, and thus tending to be held seated by the hydrostatic pressure of the liquid content of the vacuum chamber, and to be opened by the action of the suction in that chamber due to the suction connection through the port, e, which-is shown without a valve control, and thus always affords suction when the apparatus is connected with the intake manifold of the engine and the engine is running.

At the top of the Vacuum chamber, and as illustrated in thecap, G, there is provided an opening, 30, which is closed by a dia 'phragm, 31, clamped by its peripheral margin onto the margin of the opening and thus constituting a. partor element of the chamber-enclosing wall which is movable inwardly and outwardly, by virtue of its flexibility, without opening the chamber wall. As illustrated, the opening, 30, is the mouth of a recess, 12, in the under side 'of the cap, G,

the diaphragm being clamped onto the cap at the under or inner side; but at the center of the outwardly protruding boss, 13, which accommodates the recess, 12, there is provided an aperture, 14, which admits atmospheric pressure to the cavity of the boss and thus to the outer side of the diaphragm over the entire exteriorly exposed surface of the latter; so that for. the purpose of rendering the diaphragm a movable wall member, the mouth ofthe recess may be considered as it is above described, as an opening in the enclosing wall of the chamber. 7 4

At the center of the diaphragm there is secured to it a stem, 16, which extends down through the vacuum chamber, A, and at its lower end is connected to the valve, 20, the

length of the stem being such as to hold the valve seated when the diaphragm is slightly flexed inwardly with respect to the vacuum chamber. A

In the vacuum chamber a lever, L, having its fulcrum carried by a lug, 32, depending from the cap, C, has pivotally connected to it at one end a rod, 33, on which a float, 40, is mounted for sliding up and down between upper and lower stops, and 35, which are made fast on the rod at selected positions for allowing the float a predetermined range of movement up and down.

Intermediate the fulcrum of the lever, L, and the rod, 33, the lever is pivotally connected with the stem, 16, which connects the diaph agm and the valve.

The flexible and movable area of the dia phragm, 31, and the seating area of the valve, 20, are related to each other, and to the lever connections of the stem, 16, to the float, d0, so that the suction action on the valve tending to open it, and the oiij sett-ing suction action on the diaphragm tending to close it, ditler slightly, with the excess in favor of closing, without regard to the hydrostatic press ire of the liquid in the chamber, and therefore before the liquid has accumulated, and also when the float s at balanced condition, buoyed by the liquid content of the chamber, so that neither its weight nor its buoyant value exerts any force on the lever for operating the valve or the diaphragm.

Upon considering this construction it may )e understood that starting with the device empty, the float resting on the lower stop of the guide stem, if the areas of the wilvc and diaphragm exposed to suction are eflectively equal, so that the suction actions on them respectively olset each other, there will be operative for holding the valve seated, the weight of the valve and stem, plus the weight of the lever, plus the weight of the float and its guide rod, w'th the advan tage of leverage substantially doubling the value of the last two elements for holding the valve seated; and it will be seen that as the chamber fills with liquid there is added the hydrostatic pressure of the liquid increasing as the level rises.

It will also be seen that when the liquid level reaches the float, the buoyancy of the float will reduce the weight thereof operatively for holding the valve seated, eliminating that element when the liquid level. reaches the balanced plane of the float, and thereafter, while the liquid continues to rise until the float reaches the upper stop.

Under these conditions,viz., (a) eiiectively equal areas of valve and diaphragm, and (6) weight of valve, stem and levers and hydrostatic pressure of liquid, constituting the means creating excess for holding the valve seated,it will be seen that in order to overcome this excess and cause the valve to be opened, the float mustbe dimensioned for developing very substantial buoyant value by the time it is fully submerged after encountering the upper stop. Since it is important for the purpose of the invention to have the float as small as possible, it may be seen to be advisable to take advantage of the fact that the buoyancy of the float as the liquid rises diminishes its weight value for holding the valve seated concurrently with the increase of hydrostatic pressure for holding it seated. And this is done by making the effective area of the valve slightly greater than that of the diaphragm for suction action, and eli'ecting the overbalance for holding the valve seat d by the weight of the float when the chamber is emp y, and making the float of such horizontal dimension that the loss of weight value as it becomes gradually submerged is substantially oliset by the gain of hydrostatic pressure on the valve as the liquid rises, submcrging the float.

By this means the float may be made much lighter than it its weight were depended upon for constituting the over-balance of force for holding the valve seated; and the lesser weight is obtainec with a very much reduced vertical dimension of the float because of the low horizontal dimensions adopted for adapting it to oflset the hydrostatic pressure; and since the float functions both in opening the valve by its buoyancy and in closing the valve by its weight, only during the change of liquid level after the va ve is stopped at he upper stop for opening or at the lower stop for closing, it will be seen that the dii'nensioning of the float as described,broad and thin, tends to limit the action for opening and closing the valve to the shortest possible part of the periods of rise and fall respectively ot the liquid, and so tends to make the opening and closing quick or sudden, as is the purpose and efli ect of snap action devices commonly employed in vacuum tanks for that purpose to ensure against the danger of coming to balance by the valve opening or closing so slowly that the movement may be halted by the atmosphere access equaling the suction access, thus causing the apparatus to be stalled, and the construction shown as above described tends to dispense with a snap action device.

I claim:

1. An apparatus for lifting ing internal combustion engines comprising a vacuum chamber having a fuel inlet connection and having at the upper part a suction connection, and at the lower part a port arranged for fluid flow through it in both directions, whereby it admits air to the chamber simultaneously with the discharge of liquid therefrom; said port constituting the sole controlled atmosphere inlet to the chamber, a valve controlling said port, the chamber having a wall member esteriorly exposed to atmospheric pressure and which is movable inwardly and outwardly without opening the wa ll; operating connections between said. well member and said valve arranged for communicating seating movement to the valve from the inward movement or" the wall memiuel for supplyher due to vacuum in the chamber; other operating connections for opening and closlng said valve, and means for actuating said other connections controlled by the level of the liquid in the chamber. I

2. A fuel feeding devicefor internal con bustion engines comprising in combination with a vacuum chamber having a fuel inlet connection and having at the upper part a suction connectionand at the lowerpart fuel outlet; a valve controlling the fuel outlet, the chamber having a wall member which is inwardly and outwardly movable without opening the wall and which is exteriorly ere posed to atmospheric pressure; opera-ting connections extending between the fuel outlet valve and said movable wall member dimensioned and arranged for communicating to the valve from the movement ofthe movable wall member stress in opposition to the direct stress upon the valve due to the vacuum in the chamber substantially counter-balancing said direct stress; other operating connections for opening and closing the valve and means for actuating the last mentioned con nections arranged to be controlled by the level of the liquid in the chamber.

3. An apparatus for lifting fuel for supplying an internal combustion engine comprising a vacuum chamber having a fuel inlet connection and having at the upper part a suction connection and at the lower part a port arranged for fluid flow through it in both directions whereby it admits air to the chamber simultaneously with the discharge of liquid therefrom; said port constituting the sole controlled air inlet to the chamber, a valve controlling said port, the chamber having a wall member which is movable inwardly and outwardly without opening the wall and which is exteriorly exposed to atmospheric pressure; operating connections between said wall member and said valve arranged for communicating to the valve from the movement of the movable wall member stress in opposition to and substantially counter-balancing the direct stress upon the valve due to the vacuum in the chamber other operating connections for opening and closing the valve, and means actuating the last mentioned connections arranged to be con trolled by the level of the liquid in the cham her.

4. In the construction defined in claim 1, the chamber having a removable cap forming the top of the chamber, the movable wall member being in the cap, the fuel outlet be ing in the bottom of the chamber, and connections between the movable wall member and the valve being a thrust link by which the valve is suspended from the movable wall member; a float in the chamber, and operat ing connections carried by the cap and engaged with said thrust link for operating the valve by a change of level of the fioat at predetermined limits of such change; whereby all the moving and operating parts which are associated for operation of the valve are carried by the cap and may be assembled and connected on the cap and introduced into and removed from the chamber in applying and removing the cap.

5. in the construction defined in claim 1, the movable wal member being a diaphragm, the chamber wall having at the inner side a recess over which the diaphragm is mounted by its margin, the wall having an opening to the atmosphere in said recess outside the diaphragm, whereby atmospheric pressure is admitted to the outer side of the diaphragm limited'ly in comparison with the area of the diaphragm eaposed to said pressure.

6. A fuel feeding device for internal combustion engines comprising a vacuum chamber having a removable cap closing it at the upper end, said cap having suction connec.- tion and a fuel inlet, the chamber having a fuel outlet the bottom and a valve controlling said outlet, the cap having an atmospheric inlet and a flexible diaphragm mounted. in the inn er side of the cap spanning said atmosphere inlet and excluding atmosphere access to the chamber, a thrust linl: connecting the diaphragm to the outlet valve dimensioned for holding the valve seated at the normal position of the diaphragm due to atmospheric pressure within thechamber; a lever having a fulcrum carried'by the cap and being connected with the thrust link for operating the valve, and a float carried by the lever at theopposite side of its connection with its thrust link from the lever v fulcrum, said float being dimensioned as to weight and buoyancy for operating the lever for opening the valve at a predetermined high level of the liquid in the chamber and for seating the valve at a predetermined low level.

7 In the construction defined in claim 1, the fuel outlet valve being pivoted at one side to its operating connection, whereby the opening movement of said connection tends to open the valve initially at one edge and to hold it open in an inclined position, whereby thesimultaneous entry of air and discharge of liquid is facilitated.

8. An apparatus for lifting fuel for supplying internal combustion engines compris ing a'vacuum chamberhaving a fuel inlet connection and having at the upper part a suction connection and at the lower part a port arranged for fluid flow through it in both directions, whereby it admits air to the chamber simultaneously with the discharge 'of liquid therefrom, an'inwardly opening valve controlling said port, the chamber hava wall member exteriorly exposedto atmospheric pressure which is movable inwardly and outwardly without opening the wall; operating connections between said wall member and said valve arranged for communicating seating movement to the valve from the inward movement of the wall member due to vacuum in the chamber; other operating connections for opening and closing said valve, and means for actuating said other connections controlled by the level of the liquid in the chamber.

9. A fuel feeding device for internal combustion engines comprising in combination with a vacuum chamber having a fuel inlet connection, and having at the upper part a suction connection and at the lower part a fuel outlet; an inwardly opening valve con trolling the fuel outlet, the chamber having a wall member which is inwardly and outwardly movable without opening the wall, and which is exteriorly exposed to atmos pheric pressure; operating connections extending between the fuel outlet valve and said movable wall member arranged for communicating to the valve from the movement of the movable wall member stress in opposition to the direct stress upon the valve due to the vacuum in the chamber substantially counterbalancing said direct stress; other operating connections for opening and closing the valve, and means for actuating the last mentioned connections arranged to be controlled by the level of the liquid in the chamber. 7

10. An apparatus for lifting fuel for supplying an internal combustion engine comprising a vacuum chamber having a fuel inlet connection and having at the upper part a suction connection, and at the lower part a port arranged for fluid flow through it in both directions; whereby it admits air to the chamber simultaneously with the discharge of liquid therefrom, said port constituting the sole controlled air inlet to the chamber, an inwardly opening valve controlling said port, the chamber having a wall member which is movable inwardly and outwardly without opening the wall and which is exteriorly exposed to atmospheric pressure; operating connections between said wall member and said valve arranged for communicating to the valve from the movement of the movable wall member stress in opposition to and substantially counterbalancing the direct stress upon the valve due to vacuum in the chamber; other operating connections for opening and closing the valve, and means actuating the last mentioned connections arranged to be controlled by the level of the liquid in the chamber.

11. An apparatus for lifting fuel for supplying internal combustion engines comprising a vacuum chamber having a fuel inletconnection and having at the upper part a suction connection, and at the lower part a port arranged for fluid flow through it in both directions, whereby it admits air to the chamber simultaneously with the discharge of liquid therefrom, said port constituting the sole controlled atmosphere inlet to the chamber; an inwardly opening valve controlling said port, the chamber having a wall member exteriorly exposed to atmospheric pressure and which is movable inwardly and outwardly without opening the wall; operating connections between said wall member and said valve arranged for communicating seating movement to the valve from the inward movement of the wall member due to vacuum in the chamber, a float in the chamber adapted to be buoyed by the liquid content thereof, and operating connections between said float and the valve arranged for opening the valve at the limit of predetermined upward move ment of the float buoyed by the liquid and for closing the valve at the limit of predetermined downward movement of the float with its weight upon the recession of the liquid.

In testimony whereof, I have hereunto set my hand at Chicago, Illinois, this 10th day of May, 1929.

WVILLIAM H. SCHULZE. 

